In telecommunications network signaling routers, such as signal transfer points, link interface cards each maintain identical copies of signaling link tables. Each link table includes individual entries corresponding to all of the signaling links in the system. Each entry includes the signaling link, the point code or other type of network address corresponding to the signaling link, and a status and/or cost associated with the route corresponding to each signaling link. The signaling link tables are used to route messages from inbound signaling links to outbound signaling links. For example, when a message arrives at one link interface card, the link interface card examines the destination address in the message, performs a lookup in its link table to determine the outbound signaling link for the message, and forwards the message to the signaling link interface card associated with the outbound signaling link for the message.
Because an incoming signaling message can be potentially routed over any of the signaling links on any card in the system, the signaling link tables maintained by each card must be complete and consistent with each other. For example, if a link on one card goes out of service, the signaling link tables on all of the cards in a system must be updated to indicate that the link is out of service. Any delay in performing these updates can result in unnecessary backplane traffic due to messages being routed to cards whose links are out of service.
One conventional method for link table consistency checking is to use a centralized operations, administration, and maintenance (OA&M) card to periodically compare link tables in the system to each other and report inconsistencies to an operator. According to this method, the OA&M card requests that each link interface card compute a checksum of its signaling link table and forward the checksum to the OA&M card. The OA&M card then compares the checksums of the individual cards. If there is a mismatch, the OA&M card reports the fact that there has been a mismatch to an operator. The operator must then manually compare individual signaling link table entries to determine the cause of the mismatch. While this method will eventually result in detection of the link that caused the inconsistency, this method is labor intensive. In addition, if the OA&M card fails, the consistency checking of all link cards will also fail.
Accordingly, in light of these difficulties associated with conventional signaling link table consistency management, there exists a need for improved methods and systems for dynamic, distributed link table consistency management.